Ariston boilers fault codes
Ariston use a three-digit numbering scheme that is more logical than it first appears, because the first digit tells you which part of the appliance is complaining. Anything beginning 1 is the central heating circuit, 2 is domestic hot water, 3 is the internal electronics, 5 is ignition and flame detection, 6 is the air and flue side, and 7 is multi-zone heating. So a 108 and a 109 are both heating-circuit pressure faults at opposite ends of the range, while a 501 is always about flame. Ariston also distinguish a hard lockout from a warning by using a P as the middle character: 5P1 is a warning that the first ignition attempt failed, whereas 501 is the lockout that follows repeated failures.
Where the code shows on a Ariston
The code appears on the LCD split into a leading digit and a two-digit group, which is why the manual writes it as "1 08" and the display can look like it is showing two separate numbers. Read it as one code. A code with the spanner symbol alongside is a service reminder rather than a fault, and the appliance will keep running with it displayed.
How to reset a Ariston
Press the reset button on the control panel once. Ariston permit a maximum of five resets within fifteen minutes; on the sixth attempt in that window the appliance shuts down completely and can only be restarted by isolating it at the fused spur and restoring power. That limit is deliberate and it exists to stop a real fault being reset repeatedly rather than diagnosed.
Most common Ariston faults
The Ariston codes people look up most.
- 501Get it checkedNo flame was detected during ignition and the appliance has locked out. Check the gas supply and the condensate pipe before booking anyone.
- 108Usually simple to fixThe heating circuit does not contain enough water to run safely. Refill through the filling loop to about 1.2 bar and the code clears.
- 101Get it checkedThe heating circuit has overheated and the appliance has shut down. The usual reason is that water has stopped moving, not that it is firing too hard.
- 103Get it checkedThe appliance is reporting insufficient circulation — water is not moving through it fast enough. Worth acting on before it becomes an overheat.
Every Ariston fault code
7 published codes. Filtering happens in the page — every code is in the HTML.
Showing 7 of 7 codes
Ariston models
Codes can differ between generations. Check yours.
Guides that help with Ariston faults
How to repressurise a boiler
The five-minute job that resolves more no-heating calls than any other. Here is how to do it properly, and how to tell when topping up is the wrong answer.Read the guideWhat to do when your condensate pipe freezes
The single most common winter boiler fault, and one of the few you can genuinely fix yourself in fifteen minutes with a kettle and some patience.Read the guideBoiler fault codes explained: what they actually tell you
Codes look like diagnoses and are not. Understanding which family a code belongs to turns a meaningless number into a genuinely useful starting point.Read the guide
Looking for Ariston’s own support? www.ariston.com. We are not affiliated with Ariston.